1. Field of Invention
The present invention pertains to systems for providing an approximate count of small fungible products, such as seeds and plastic pellets. More particularly the present invention relates to determining the density of the fungible products in a unit volume in an associated or parallel product flow so the system or a separate connected system can dispense a close approximation of a specific quantity based on the volume calculation derived from product density rather than dispensing by estimated weight only. The user now has the ability to vary the weight in order to achieve a very accurate piece count.
2. Description of the Related Art
Processing operations for seeds provide a clear background for the present type of system. In traditional seed processing operations, the operator receives bulk deliveries of the desired seed, which include undesirable elements in each delivery; which may also include hulls, rocks, insects, plant matter, weed seeds, and pieces of desirable seeds. The operator utilizes various equipment to remove these undesirable constituents, leaving only whole desired seeds. This may include receiving, cleaning, treating, potentially storing, and packing seed for purchase, typically by weight. While purchase by actual number of seeds is desirable, due to variations in source and timing, in processing to remove undesirable constituents, the number of seeds per unit weight, the seed density, varies. Additionally, when seeds of differing suppliers are combined, the seeds received may vary in size and moisture content yielding much different densities from supplier to supplier. Due to these variations, operators have historically been unable to accurately deliver a specific number of seeds per package, where the package in question may range from fifty (50) pounds to ten thousand (10,000) pounds. This creates issues for purchasers, among others, who desire to purchase a certain quantity of seeds, typically enough for seeding of a particular area but not so much as to have leftover, and often thereafter unusable, seed. Leftover seed may be unusable because of storage issues, germination period, and, particularly with the rise of genetically-modified and patented seeds, most importantly legal permissions. Thus, inconsistent seed counts can create substantial issues, sometimes providing an insufficient or wasteful quantity of seeds when computed on the anticipated planting rate. When attempting to provide seeds based on quantity, operators have intentionally underestimated the number of seeds likely to be a particular weight bag so as to guarantee purchasers receive enough seed. This, however, results in waste as unnecessary, and therefore unusable, seed is provided to purchasers. Moreover, operators lose potential revenues on each sale solely to ensure sufficient seeds per sale. Regulatory authorities are requiring the industry begin labeling the seed packaging with the “count” or number of seeds per container. In addition the processor may desire to purchase seeds by the count rather than weight. While not tested for this application the invention could provide utility in this and many other bulk product handling facilities.
Attempts to provide accurate seed counts have focused on providing a true count of seeds by processing each seed through a counter. One attempt at resolving this situation has provided for each single seed to be drawn past a photoelectric sensor and individually counted. In another attempt, a sampling of seeds is vibrated past a series of photodetector cells or seed counters and individually counted, and then weighed, to determine a theoretical mass for the desired seed count. Problematically, these systems require that each seed be actually counted, which results in substantial reduction in speed of processing and which does not adequately address the issue of broken seeds, and of distinguishing individual seeds which are larger than the standard size from clusters of seeds. In another attempt in the prior art, an image of uniformly-sized, and ideally uniformly-distributed, seeds on a horizontal surface is processed to determine average object size and extrapolated to determine an estimated total object count for the imaged seeds. Problematically, this system provides only a estimated count based on computer average size based on a single review and provides no means to limit the count being directed to a bag or other output. Moreover, the requirement of a uniform size of seeds can create issues as seed size may vary significantly. Unequal distribution, particularly due to clusters of seeds, skews the results.
Additionally, attempts to modify existing systems to include equipment to provide accurate seed counts have been economically unfeasible, requiring line retooling and capital investment and utilizing systems generating stale data. The current systems require, in some cases, as much as 30 minutes to determine the applicable density data. In such cases, by the time the density date is available, the density of the passing product may have substantially deviated from the determination, providing data of little utility.
Thus, there is a need in the art for a system for use in product processing operations that rapidly determines the density of products, which may be used to obtain a desired product count per bag with little waste and which can do so by eliminating broken products from the count, counting the products within clusters, and counting products of varying sizes. Moreover, there is a need for a system which integrates easily into existing operations and the current product handling systems without excessive line retooling and without substantial capital investment. There is also a need for a system which integrates with the current plant information and control systems along with the weigh-bagger to provide an accurate method for dispensing a weight that contains a very accurate number of objects (seeds), particularly one designed to work in-line and support high volume operations.